IRR Calculator
Calculate the internal rate of return (IRR) for an investment using an iterative Newton-Raphson solver. Enter your initial investment and up to 10 years of expected cash flows to find the discount rate that makes the net present value equal to zero.
Internal Rate of Return (IRR) is the discount rate at which an investment's net present value (NPV) equals zero — equivalently, the implied annualized return of an investment's cash flow stream. If you invest $100,000 today and receive specific cash flows over the next 5 years, the IRR is the single annual rate that exactly balances the upfront cost against the present value of all future cash flows.
The metric is everywhere in serious investing: private equity LPs evaluate fund managers on IRR, real estate investors quote IRR on deals, corporate finance teams use it for capital budgeting (project A IRR 18% vs project B IRR 12%), and venture investors track IRR across their portfolios. IRR is the natural metric whenever cash flows are irregular — multiple deposits, withdrawals, or returns happening at different points in time — because simpler measures like CAGR can't handle that complexity.
This calculator uses Newton-Raphson iteration to solve for the IRR given an initial investment and up to 5 years of cash flows. The output is a single annualized return. Use it for project evaluation, real estate deal analysis, comparing investment alternatives with different timing, and stress-testing assumptions. The result is meaningful only when compared to your hurdle rate (the minimum return you require to make the investment worthwhile) — an IRR of 14% is great if your hurdle rate is 10% and mediocre if your hurdle rate is 18%.
Inputs
Results
Internal Rate of Return
13.45%
Total Cash Inflows
$150,000
Net Return
$50,000
Payback Period
3.7 years
Cash Flows by Year
Cash Flow Analysis
| Year | Cash Flow | Cumulative | Present Value |
|---|---|---|---|
| 0 | $-100,000.00 | $-100,000.00 | $-100,000.00 |
| 1 | $20,000.00 | $-80,000.00 | $17,628.43 |
| 2 | $25,000.00 | $-55,000.00 | $19,422.59 |
| 3 | $30,000.00 | $-25,000.00 | $20,543.39 |
| 4 | $35,000.00 | $10,000.00 | $21,125.28 |
| 5 | $40,000.00 | $50,000.00 | $21,280.31 |
Formula
How to use this calculator
- Enter the initial investment as a positive number — the amount of cash committed at time zero.
- Enter each subsequent year's expected cash flow. Positive numbers represent income or distributions to you; negative numbers represent additional capital calls. Most simple projects have all-positive cash flows after year 0.
- Review the IRR. It's the single annualized rate the project effectively pays you over its life.
- Compare IRR to your hurdle rate (the minimum return you require). If IRR > hurdle, the project creates value at your required return. If IRR < hurdle, walk away.
- For real estate or business-deal analysis, ensure cash flows include both operating cash flow each year AND the terminal sale/exit value in the final year (which often dominates the IRR).
- For sensitivity, rerun with conservative cash flow assumptions (lower revenues, higher expenses, lower exit value) to see how robust the IRR is. Deals that only work under optimistic assumptions usually don't.
- For projects with non-conventional cash flows (multiple sign changes — e.g., requiring additional investment in year 3), be aware that IRR can have multiple valid solutions. Use NPV at your specific hurdle rate instead in those cases.
Worked examples
Real estate flip — 18-month timeline
Buy property for $200,000 in cash. Renovation costs $50,000 in year 1. Sell for $310,000 in year 2 (18 months). Initial investment: $200,000 Year 1 cash flow: −$50,000 (renovation) Year 2 cash flow: $310,000 (sale) Solving for IRR: approximately 14.5% annualized. The simple total return is ($310K − $200K − $50K) / $250K = 24% — but that ignores the time value. IRR correctly accounts for the renovation occurring a year later and gives the annualized rate.
Small business buyout — 5-year hold
Buy a small business for $500,000. Operating cash flows: $80K, $100K, $120K, $140K, $160K. Sell business at end of year 5 for $750,000. Initial investment: $500,000 Year 1: $80,000 Year 2: $100,000 Year 3: $120,000 Year 4: $140,000 Year 5: $160,000 + $750,000 = $910,000 Solving for IRR: approximately 26% annualized. A strong return if achievable. The terminal sale value dominates — IRR drops dramatically if the exit comes in at $500K (no appreciation) instead of $750K.
Comparing two projects of different lengths
Project A: Invest $100K, returns $130K in year 2. Total return 30%, time 2 years. Project B: Invest $100K, returns $200K in year 5. Total return 100%, time 5 years. Project A IRR: (130/100)^(1/2) − 1 ≈ 14.0% Project B IRR: (200/100)^(1/5) − 1 ≈ 14.9% Despite Project B having far higher total return, the IRRs are within 1% of each other. Without time-adjusting via IRR, Project B looks far better; properly compared, they're nearly equivalent annualized returns.
When to use this calculator
Use this calculator for any investment with cash flows occurring at multiple points in time — real estate deals (purchase + operating cash flow + sale proceeds), business buyouts (purchase + operating + exit), corporate capital projects (investment + ramp + steady-state cash flow), and private investment positions where capital calls and distributions happen at different times.
IRR is the right tool when you need a single annualized return number that handles irregular cash flows. CAGR handles only beginning-and-ending values with nothing in between; IRR handles arbitrary cash flow schedules. NPV handles the same cash flows but requires a discount rate as input rather than producing one.
Pair this with the NPV calculator (its mirror — given a discount rate, find the value; IRR is the discount rate that makes value zero), the ROI calculator (simpler total-return measure, not time-adjusted), and the CAGR calculator (when there are no intermediate cash flows).
A few caveats: IRR assumes interim cash flows are reinvested at the IRR — a strong assumption that's often not realistic. For more accurate ranking of competing projects, look at NPV at a specific hurdle rate or Modified Internal Rate of Return (MIRR) which uses a separate reinvestment rate. IRR can also produce multiple mathematical solutions when cash flows change sign more than once (e.g., investment, returns, then another investment) — in those cases, fall back to NPV.
For everyday investment analysis, IRR is the standard. For PE, VC, and real estate, IRR is the industry-standard performance metric. Knowing how to read it correctly — and what its limitations are — separates serious investment analysis from amateur work.
Common mistakes to avoid
- Comparing IRRs from projects of different lengths without context. A 5-year project IRR and a 2-year project IRR are both annualized, so technically comparable — but the longer project's IRR depends on more years of cash flow assumptions and is more uncertain.
- Ignoring the reinvestment assumption. IRR assumes cash flows can be reinvested at the IRR. If your IRR is 25% but your realistic reinvestment opportunity is 7%, the actual realized return on the entire dollar stream will be lower. Modified IRR (MIRR) addresses this by allowing a separate reinvestment rate.
- Falling for high IRRs on small deals. A small deal with a 50% IRR and total profit of $10K is less valuable than a large deal with 15% IRR and total profit of $500K. IRR doesn't capture absolute dollar return — combine it with NPV or total profit for the complete picture.
- Forgetting that IRR is annualized. If your investment makes "100% return" in 6 months, the IRR is much higher than 100% (compounded). Conversely, "100% return" in 10 years has an IRR of only ~7%.
- Using IRR on cash flow streams with multiple sign changes. If cash flows go negative, positive, negative, positive, the IRR equation can have multiple solutions. Use NPV at a specific discount rate instead — it has only one answer.
- Treating IRR as a quality score independent of hurdle rate. An 18% IRR is fantastic if your hurdle is 12% and unacceptable if your hurdle is 22%. Always evaluate IRR against the appropriate risk-adjusted required return.
Frequently Asked Questions
Sources & further reading
- Internal Rate of Return — Capital Budgeting Concepts — U.S. Securities and Exchange Commission
- Discounted Cash Flow Analysis — fundamentals — U.S. Securities and Exchange Commission
- FINRA — Key Investing Concepts — Financial Industry Regulatory Authority